On Oct 23, Bill Wood wrote:
> On Mon, 2006-10-23 at 22:12 -0400, Eli Barzilay wrote:
> > On Oct 24, Dan Muresan wrote:
> > > > * the ability to catch bugs in code that wants to use lists of equal
> > > > length
> > >
> > > (you mean unequal length)
> >
> > No -- code that wants equal-length lists, but got unequal lengths
> > instead. Before your change it raised an error and got a happy
> > programmer. After your change you get a bug that propagates further
> > and becomes harder to find.
>> Doesn't that work both ways? [...]
Of course. Like I said, the question is which version gives you the
the most benefits. (And allowing more inputs is not always more
benefits.)
> I have a weakly justifiable preference for the CL behavior on the
> grounds that a) maps over unequal length lists have a sensible
> specification and b) robust design favors weakening the input
> constraint.
Justifications for either side would be good (BTW, I'm don't have a
preference either way -- I'm not sure which version is better.), but I
don't think that your arguments hold. Your first argument is bogus,
since `map' over equal length lists is also sensible. The second
argument is questionable too -- and there are (IMO) too many languages
that suffer from that when they deal with strings, integers, and `+'.
For example, where's the bug in this code
function add1_to_x() {
document.form.y.value = document.form.x.value + 1;
}
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://www.barzilay.org/ Maze is Life!